My mod wish list is quite extensive:
Cold waves
Cold wave countermeasures do not make much sense to me. I’d like to see a heat management system, with buildings producing waste heat, which then can be piped to buildings to be warmed. Also solar collectors and heat pumps that can produce more heat and store it underground for later retrieval. Replacing the subsurface heater, which I absolutely am at loss how it is supposed to be useful, as minimising heat conductivity to ground would be one of my first engineering measures to counter cold waves.
Recycling
I’d like to see water recovery and refinery systems implemented, with waste water being produced by
water consumers. I’d also like to see CO2 being implemented as resource that is necessary for oxygen generation and also rocket fuel production. (At least as an option, but Methane is definitely easier to store on Mars than LH, and also preferable as jet fuel)
Plants likewise should require CO2 and produce O2 (and not just reduce consumption, so you can eventually get all your O2 from plants. Similarly I’d much prefer oxygen consumption by colonist, and at some point also farm animals, hopefully.
Metal refinery
Picking up random asteroids and building a dome out of it seems a bit too easy, some kind of foundry should be necessary to produce structurally useable material. This will of course require some serious energy.
Various rocket transport options
- I’d like to see some variety, from disposable 1-way transports which possibly cannot transport sensitive goods due to rough landing.
- Ion-thruster ferries with orbital shuttles/decent capsules, which can carry a massive amount of cargo, but are expensive to build in the first place. The decent capsules may either be reusable, or also parachute landers may be used for material delivery.
- Per-Launch costs for the BFR clone standard rocket, with reduced inventory on the trip back as it needs to both perform an orbital launch and an interplanetary burn.
- Dedicated cargo variants, as life support for a year long trip is heavy, you do not want to carry that around if you don’t need to. Similarly, sending 1 colonist should be almost as expensive as filling the whole ship
- Rocket damage+malfunctions, these would be rare but possibly life threatening emergencies, also having to launch rescue missions for a rocket that landed way off course could be interesting, and there should be an incentive to land rockets away from anything critical.